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Birth weight and early growth have been associated with later blood pressure. However, not all studies consistently find a significant reduction in blood pressure with an increase in birth weight. In addition, the relative importance of birth weight and of other lifestyle and environmental factors is often overlooked and the association is rarely studied in adolescents. We investigated early life predictors, including birth weight, of adolescent blood pressure in the Gateshead Millennium Study (GMS). The GMS is a cohort of 1029 individuals born in 1999–2000 in Gateshead in Northern England. Throughout infancy and early childhood, detailed information were collected, including birth weight and measures of height and weight. Assessments of 491 returning participants at age 12 years included measures of body mass and blood pressure. Linear regression and path analysis were used to determine predictors and their relative importance on blood pressure. Birth weight was not directly associated with blood pressure at the age of 12. However, after adjustment for contemporaneous body mass index (BMI), an inverse association of standardized birth weight on systolic blood pressure was significant. The relative importance of birth weight on later systolic blood pressure was smaller than other contemporaneous body measures (height and BMI). There was no independent association of birth weight on blood pressure seen in this adolescent population. Contemporaneous body measures have an important role to play. Lifestyle factors that influence body mass or size, such as diet and physical activity, where interventions are directed at early prevention of hypertension should be targeted.
Giardia duodenalis and Cryptosporidium spp. are common intestinal protozoa that can cause diarrhoeal disease. Although cases of infection with Giardia and Cryptosporidium have been reported in Alaska, the seroprevalence and correlates of exposure to these parasites have not been characterised. We conducted a seroprevalence survey among 887 residents of Alaska, including sport hunters, wildlife biologists, subsistence bird hunters and their families and non-exposed persons. We tested serum using a multiplex bead assay to evaluate antibodies to the Giardia duodenalis variant-specific surface protein conserved structural regions and to the Cryptosporidium parvum 17- and 27-kDa antigens. Approximately one third of participants in each group had evidence of exposure to Cryptosporidium. Prevalence of Giardia antibody was highest among subsistence hunters and their families (30%), among whom positivity was associated with lack of community access to in-home running water (adjusted prevalence ratio [aPR] 1.15, 95% confidence interval (CI) 1.02–1.28) or collecting rain, ice, or snow to use as drinking water (aPR 1.09, 95% CI 1.01–1.18). Improving in-home water access for entire communities could decrease the risk of exposure to Giardia.
To achieve high yields of total solids in a dairy herd requires the implementation of appropriate breeding and feeding strategies. The Edinburgh School of Agriculture's Langhill herd, which consists of 200 cows, embarked on a long-term breeding programme in the early 1970s to demonstrate to what extent genetic improvement might be achieved within a herd, using selection methods available to commercial dairy farmers. The specific selection objective was yield of total solids, with artificial insemination (AI) sires being chosen on their improved contemporary comparison for fat plus protein production and females being selected on their genetic index for the same traits. To measure genetic change, a genetic control population was established. Thus, a section of the herd, currently 25 animals but increasing to 20% of the total herd, are bred from a panel of 50 AI sires selected randomly from the 1976 Milk Marketing Board and Scottish Milk Marketing Board Dairy Bull Progeny Testing Schemes. The herd is given complete diets during the winter housing period, September to May, and grazed on a paddock system in the summer months. The average 305-day yield in the selected herd in 1983 was 6924 kg at 41.8 g fat and 34.2 g protein/kg. This yield shows an increase from the 1977 yield of 5732 kg at 38.7 g fat and 32.5 g protein/kg. Current first-lactation yields average 6107 kg at 42.5 g fat and 33.9 g protein/kg. The food intake of a section of the herd is recorded and initial results suggest that cows producing high yields of solids are more efficient than cows producing lower yields.
The Star Centre is a national astronomy and space science base which
facilitates public access to news and information
promotes public awareness, interest, enjoyment and understanding.
The Star Centre meets these twin aims by providing an information service which can be accessed in a variety of ways and by offering a menu of public observing events.
The concept of a national astronomy base developed as part of the Centre for Science Educations growing portfolio of initiatives in both the formal education sector and the wider umbrella of the Public Understanding of Science. In December 1996 the Star Centre was launched with the aid of a Royal Society COPUS development grant and matching funding from Sheffield Hallam University.
Helicobacter pylori infection is a major cause of peptic ulcer and is also associated with chronic gastritis, mucosa-associated lymphoid tissue (MALT) lymphoma, and adenocarcinoma of the stomach. Guidelines have been developed in the United States and Europe (areas with low prevalence) for the diagnosis and management of this infection, including the recommendation to ‘test and treat’ those with dyspepsia. A group of international experts performed a targeted literature review and formulated an expert opinion for evidenced-based benefits and harms for screening and treatment of H. pylori in high-prevalence countries. They concluded that in Arctic countries where H. pylori prevalence exceeds 60%, treatment of persons with H. pylori infection should be limited only to instances where there is strong evidence of direct benefit in reduction of morbidity and mortality, associated peptic ulcer disease and MALT lymphoma and that the test-and-treat strategy may not be beneficial for those with dyspepsia.
We performed a study to determine rates of reinfection in three groups followed for 2 years after successful treatment: American Indian/Alaska Native (AI/AN) persons living in urban (group 1) and rural (group 2) communities, and urban Alaska non-Native persons (group 3). We enrolled adults diagnosed with H. pylori infection based on a positive urea breath test (13C-UBT). After successful treatment was documented at 2 months, we tested each patient by 13C-UBT at 4, 6, 12 and 24 months. At each visit, participants were asked about medication use, illnesses and risk factors for reinfection. We followed 229 persons for 2 years or until they became reinfected. H. pylori reinfection occurred in 36 persons; cumulative reinfection rates were 14·5%, 22·1%, and 12·0% for groups 1, 2, and 3, respectively. Study participants who became reinfected were more likely to have peptic ulcer disease (P = 0·02), low education level (P = 0·04), or have a higher proportion of household members infected with H. pylori compared to participants who did not become reinfected (P = 0·03). Among all three groups, reinfection occurred at rates higher than those reported for other US populations (<5% at 2 years); rural AI/AN individuals appear to be at highest risk for reinfection.
Neutrinos are one of the major puzzles in modern physics. Despite measurements of mass differences, the Standard Model of particle physics describes them as exactly massless. Additionally, recent measurements from both particle physics experiments and cosmology indicate the existence of more than the three Standard Model species. Here, we review the cosmological evidence and its possible interpretations.
A heuristic greedy algorithm is developed for efficiently tiling spatially dense redshift surveys. In its first application to the Galaxy and MassAssembly (GAMA) redshift survey we find it rapidly improves the spatial uniformity of our data, and naturally corrects for any spatial bias introduced by the 2dF multi-object spectrograph. We make conservative predictions for the final state of the GAMA redshift survey after our final allocation of time, and can be confident that even if worse than typical weather affects our observations, all of our main survey requirements will be met.
This chapter concentrates on recent robust advances that are likely to affect clinical care over the short to medium term. It discusses potential biomarkers for stratified treatment of high-grade serous (HGSOC) and their relationship with platinum sensitivity and resistance. The accurate diagnosis of sub-type before chemotherapy treatment is vital as it provides strong prognostic and biological information. Many expression microarray studies have attempted to define prognostic and predictive signatures for chemoresistance in epithelial ovarian cancer (EOC). DNA copy number analysis has also been investigated as a predictive marker. Ultrasound- or computed tomography (CT)-guided biopsy is the standard of care for initial diagnosis of women with suspected ovarian cancer. Intratumoral genetic heterogeneity in HGSOC has been demonstrated both within a region of tumour and between different metastatic sites. These genetic differences could be expected to alter chemosensitivity.
We report the observation of an ultrafast (~ 430 fs) charge transfer process
at the interface between a single-walled carbon nanotube (SWNT) wrapped by a
semi-conducting polymer, poly(3-hexylthiophene) (P3HT), creating free
polarons on both materials. The addition of excess P3HT as a surrounding
network allows these free polarons to be long-lived at room temperature. Our
results suggest that SWNT-P3HT blends incorporating only 1% fractions of
SWNTs can achieve a charge separation efficiency comparable to a
conventional 60:40 P3HT-fullerene blend, provided small-diameter tubes are
embedded in an excess P3HT matrix.
The growth of copper, silver and gold thin films on tungsten disulfide has been examined as a model of metal contacts on a layered semiconductor. All three metals were found to grow epitaxially on the WS2. However, Cu appears to form a discontinuous film while Au and Ag grow layer by layer. Such epitaxial growth is somewhat surprising since there is a large lattice mismatch between the metals and the WS2.
Silicon carbide whiskers have excellent mechanical and chemical properties, making them very desirable as a reinforcement for structural ceramic and other composite materials. Los Alamos has developed a laboratoryscale batch process for producing very high quality SiC whiskers by the vapor-liquid-solid (VLS) method which is an active candidate for technology transfer involving significant scale-up. The process, however, involves quite complex chemical/physical and parametric relationships and has not as yet lent itself successfully to modeling. An expert computer system was therefore developed to facilitate the transfer of this technology to industry. Optimum conditions were determined by relating the many process parameters to product results to establish a set of rules for running the process. These are incorporated in a two-phase expert system designed to guide inexperienced users. In Phase I, an expert consultant program provides the user with information that enables him to set up the run. This information is incorporated into the rule base that makes up Phase II- the control system. At present, the operator functions as the controller by responding to the decisions of the expert system; automation can be added later.
By 1973 the last populations of the Bush Elephant (Loxondonta africana africana) in the Republic of Rwanda comprised two small groups of ca 70 animals each. Both were surrounded by expanding human settlement which caused rising conflict between Elephants and Man. Eventually the elephants' removal became imperative. Adults (103) and unweaned immatures (3) were therefore shot.
Ion acoustic waves propagating in a collision-free gravity-supported one-dimeiisional plasma are studied, including conditions where the wavelength is of the order of the scale height of the equilibrium plasma. It turns out that the fluid dynamic steepening tendency of waves propagating in the direction of decreasing density is overcome by Landau damping up to wavelengths of the order of the scale height or even larger, depending on the ratio of the electron and the ion temperatures.
Exospheric atomic hydrogen escaping from the planet HD 209458b provides the largest observational signature ever detected for an extrasolar planet atmosphere. We present observations of this transiting planet's extended exosphere with the Advanced Camera for Surveys on board the Hubble Space Telescope. From the two transit light curves obtained at Lyman α, we find an in-transit absorption of (8.0±5.7)%, in good agreement with previous studies. These new constraints on the size of the exosphere strengthens the evaporation scenario. Full details are provided in Ehrenreich et al. (2008).
Living systems exert exquisite control on all aspects of biomineral production and organic components, including proteins, are essential to this biological control. The protein-rich extrapallial (EP) fluid of bivalve molluscs is a strong candidate for the source of such proteins. Differences in calcium carbonate polymorphs between Modiolus modiolus and Mytilus edulis are concurrent with differences in EP fluid protein profiles. In conjunction with this biological control is the environmental influence which is interpreted using proxies such as δ18O to determine the history of ambient seawater temperature. In the horse mussel, Modiolus modiolus, the difference in oxygen isotope fractionation in the nacreous aragonite and the prismatic aragonite layer results in respective δ18O values of 2.1±0.2% and 2.5±0.2%. These δ18O values result in estimates of ambient seawater of 12.1±0.6°C and 10.2±0.6°C for nacreous and prismatic aragonite, respectively. Electron backscatter diffraction is used here to determine the crystallographic orientation at high spatial resolution, allowing the measurements of stable isotopes to be accurately mapped in terms of shell architecture. These preliminary data suggest that it is essential to account for both polymorph and crystal habit when deciphering ambient seawater temperature using δ18O as a proxy.
With their long geological history and stable low-Mg calcite shells, Rhynchonelliform brachiopods are attractive sources of environmental data such as past seawater temperature (Buening and Spero, 1996; Auclair et al., 2003; Brand et al., 2003; Parkinson et al., 2005). Concerns about the influence of vital effects on the stable isotope composition of brachiopod shells (Popp et al., 1986), led to isotope analyses of different parts of brachiopod shells in order to identify those parts of the shell that are influenced by any vital effect and those parts that may be suitable recorders of seawater temperature via stable oxygen isotope composition (Carpenter and Lohmann, 1995; Parkinson et al., 2005). Such detailed studies demonstrated that the outer primary layer of acicularcalcite is isotopically light in both δ18O and δ13C while the secondary layer, composed of calcite fibres, is in oxygen-isotope equilibrium with ambient seawater(Fig. 1) (Parkinson et al., 2005).
Over 150 extrasolar planets are known to orbit sun-like stars. A growing number of them (9 to date) are transiting “hot Jupiters” whose physical characteristics can be measured. Atmospheres of two of these planets have already been detected. We summarize the atmosphere detections and useful upper limits, focusing on the MOST albedo upper limit and II exosphere detection for IID 209458b as the most relevant for photochemical models. We describe our photochemical model for hot Jupiters and present a summary explanation of the main results: a low gas-phase abundance of hydrocarbons; an absence of hydrocarbon hazes; and a large reservoir of II atoms in the upper atmospheres of hot Jupiters. We conclude by relating these model results to the relevant observational data.